1. Field of the Invention
The present invention relates to electric storage batteries and, more particularly, to improvements in battery casing covers.
2. Description of the Prior Art
In general, storage batteries have multiple cells with lead plates surrounded by electrolyte. Depending on battery use, frequency of recharging and climatic conditions, the electrolyte evaporates and must be replenished to maintain the desired battery output. This is usually accomplished by removing a vented fill plug from each cell and pouring the liquid electrolyte through inlets above each cell. This, of course, is cumbersome and time-consuming--particularly where electrolyte replenishment is required on a frequent basis.
With the advent of electric powered vehicles or the everyday use of electric golf carts and forklift trucks, nightly recharging and electrolyte addition is a necessity. In such cases, a large number of storage batteries are involved with an even larger number of fill plugs.
To minimize plug handling, sliding covers were designed to close the cell inlets. U.S. Pat. Nos. 1,269,096 and 2,697,129 describe a plate that may be slid over the fill opening or swung thereover about a pivot. The flat plate underside and flat area about the inlet mate to form a seal.
A disadvantage of the above is that heat and chemical corrosion tend to warp the slide thus rendering ineffective the seal. This allows spillage and excess evaporation to occur. Also, a separate slide assembly is required for each cell opening.
A sliding cover for multiple cell fill inlets is shown in U.S. Pat. No. 3,218,198. In this construction, the slide seals along the upper periphery of a trough and the cell openings are located in the bottom of the trough. Because each cell is in communication with each other via the trough, contamination or a problem with one will be transferred and/or impact on the others. Note that a common problem with battery maintenance is the use of improper electrolyte or allowing grease, dirt, cleaners or other contaiminants to enter a cell. With the above system, all cells will be harmed instead of just one as before.